40 I believe because the space of the auto mobile catching up to the train is 4 hours. 4 times 30 is 120 miles so u need to figure out a number that can reach 120 in three hours. 3 times 40 is 120
Answer:
j=46
Step-by-step explanation:
34=j-12
add 12 to 34 to isolate j
the answer to that is 46
j=46
The height of the prism is 12 feet.
Answer:
21120 hours long
Step-by-step explanation:
42240=20 miles
42240/2=21120h